/*
	ClusterMarker Version 1.2.1

	A marker manager for the Google Maps API
	http://googlemapsapi.martinpearman.co.uk/clustermarker
	
	Copyright Martin Pearman 2008.
	Last updated 2nd February 2008

	This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

	This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more details.

	You should have received a copy of the GNU General Public License along with this program.  If not, see <http://www.gnu.org/licenses/>.
	
*/

function ClusterMarker($map, $options){
	this._map=$map;
	this._mapMarkers=[];
	this._iconBounds=[];
	this._clusterMarkers=[];
	this._eventListeners=[];
	if (typeof($options)=='undefined'){
		$options={};
	}
	this.borderPadding=($options.borderPadding)?$options.borderPadding:256;
	this.clusteringEnabled=($options.clusteringEnabled===false)?false:true;
	if ($options.clusterMarkerIcon){
		this._clusterMarker.icon=$options.clusterMarkerIcon;
	} else {
		this._clusterMarker.icon=new GIcon();
		this._clusterMarker.icon.image='http://maps.google.com/mapfiles/arrow.png';
		this._clusterMarker.icon.shadow='http://www.google.com/intl/en_us/mapfiles/arrowshadow.png';
		this._clusterMarker.icon.shadowSize=new GSize(39, 34);
		this._clusterMarker.icon.iconSize=new GSize(39, 34);
		this._clusterMarker.icon.iconAnchor=new GPoint(9, 33);
	}
	this.clusterMarkerTitle=($options.clusterMarkerTitle)?$options.clusterMarkerTitle:'Click to zoom in and see %count markers';
	if ($options.fitMapMaxZoom){
		this.fitMapMaxZoom=$options.fitMapMaxZoom;
	}
	this.fitMapToMarkers=($options.fitMapToMarkers===false)?false:true;
	this.intersectPadding=($options.intersectPadding)?$options.intersectPadding:0;
	if ($options.markers){
		this.addMarkers($options.markers);
	}
	GEvent.bind(this._map, 'moveend', this, this._moveEnd);
	GEvent.bind(this._map, 'zoomend', this, this._zoomEnd);
	GEvent.bind(this._map, 'maptypechanged', this, this._mapTypeChanged);
}

ClusterMarker.prototype.addMarkers=function($markers){
	for (var i=$markers.length-1; i>=0; i--){
		//	check all these properties must be set
		$markers[i]._isVisible=false;
		$markers[i]._isActive=false;
		$markers[i]._makeVisible=false;
	}
	if (this.fitMapToMarkers){
		var $markersBounds=new GLatLngBounds();
		for (i=$markers.length-1; i>=0; i--){
			$markersBounds.extend($markers[i].getLatLng());
		}
		var $fitMapToMarkersZoom=this._map.getBoundsZoomLevel($markersBounds);
		
		if (this.fitMapMaxZoom && $fitMapToMarkersZoom>this.fitMapMaxZoom){
			$fitMapToMarkersZoom=this.fitMapMaxZoom;
		}
		this._map.setCenter($markersBounds.getCenter(), $fitMapToMarkersZoom);
	}
	this._mapMarkers=$markers;
	this._iconBounds=[];
};

ClusterMarker.prototype._clusterMarker=function($clusterGroupIndexes){
	var $clusterGroupBounds=new GLatLngBounds(), i, $clusterMarker, $map=this._map;
	for (i=$clusterGroupIndexes.length-1; i>=0; i--){
		$clusterGroupBounds.extend(this._mapMarkers[$clusterGroupIndexes[i]].getLatLng());
	}
	//	var $title=this.clusterMarkerTitle.replace(/%count/gi, $clusterGroupIndexes.length);
	$clusterMarker=new GMarker($clusterGroupBounds.getCenter(), {icon:this._clusterMarker.icon, title:this.clusterMarkerTitle.replace(/%count/gi, $clusterGroupIndexes.length)});
	$clusterMarker._clusteredMarkers=$clusterGroupIndexes;
	this._eventListeners.push(GEvent.addListener($clusterMarker, 'click', function(){
		$map.setCenter($clusterGroupBounds.getCenter(), $map.getBoundsZoomLevel($clusterGroupBounds));
	}));
	return $clusterMarker;
};

ClusterMarker.prototype._filterActiveMapMarkers=function(){
	var $borderPadding=this.borderPadding, $mapZoomLevel=this._map.getZoom(), $mapProjection=this._map.getCurrentMapType().getProjection(), $mapPointSw, $activeAreaPointSw, $activeAreaLatLngSw, $mapPointNe, $activeAreaPointNe, $activeAreaLatLngNe, $activeAreaBounds=this._map.getBounds(), i, $marker, $uncachedIconBoundsIndexes=[], $oldState;
	if ($borderPadding) {
		$mapPointSw=$mapProjection.fromLatLngToPixel($activeAreaBounds.getSouthWest(), $mapZoomLevel);
		$activeAreaPointSw=new GPoint($mapPointSw.x-$borderPadding, $mapPointSw.y+$borderPadding);
		$activeAreaLatLngSw=$mapProjection.fromPixelToLatLng($activeAreaPointSw, $mapZoomLevel);
	
		$mapPointNe=$mapProjection.fromLatLngToPixel($activeAreaBounds.getNorthEast(), $mapZoomLevel);
		$activeAreaPointNe=new GPoint($mapPointNe.x+$borderPadding, $mapPointNe.y-$borderPadding);
		$activeAreaLatLngNe=$mapProjection.fromPixelToLatLng($activeAreaPointNe, $mapZoomLevel);
	
		$activeAreaBounds.extend($activeAreaLatLngSw);
		$activeAreaBounds.extend($activeAreaLatLngNe);
	}
	this._activeMarkersChanged=false;
	if (typeof(this._iconBounds[$mapZoomLevel])=='undefined') {
		//	no iconBounds cached for this zoom level
		//	no need to check for existence of individual iconBounds elements
		this._iconBounds[$mapZoomLevel]=[];
		this._activeMarkersChanged=true;	//	force refresh(true) as zoomed to uncached zoom level
		for (i=this._mapMarkers.length-1; i>=0; i--){
			$marker=this._mapMarkers[i];
			$marker._isActive=$activeAreaBounds.containsLatLng($marker.getLatLng())?true:false;
			$marker._makeVisible=$marker._isActive;
			if ($marker._isActive) {
				$uncachedIconBoundsIndexes.push(i);
			}
		}
	} else {
		//	icondBounds array exists for this zoom level
		//	check for existence of individual iconBounds elements
		for (i=this._mapMarkers.length-1; i>=0; i--){
			$marker=this._mapMarkers[i];
			$oldState=$marker._isActive;
			$marker._isActive=$activeAreaBounds.containsLatLng($marker.getLatLng())?true:false;
			$marker._makeVisible=$marker._isActive;
			if (!this._activeMarkersChanged && $oldState!=$marker._isActive) {
				this._activeMarkersChanged=true;
			}
			if ($marker._isActive && typeof(this._iconBounds[$mapZoomLevel][i])=='undefined') {
				$uncachedIconBoundsIndexes.push(i);
			}
		}
	}
	return $uncachedIconBoundsIndexes;
};

ClusterMarker.prototype._filterIntersectingMapMarkers=function(){
	var $clusterGroup, i, j, $mapZoomLevel=this._map.getZoom();
	for (i=this._mapMarkers.length-1; i>0; i--)
	{
		if (this._mapMarkers[i]._makeVisible){
			$clusterGroup=[];
			for (j=i-1; j>=0; j--){
				if (this._mapMarkers[j]._makeVisible && this._iconBounds[$mapZoomLevel][i].intersects(this._iconBounds[$mapZoomLevel][j])){
					$clusterGroup.push(j);
				}
			}
			if ($clusterGroup.length!==0){
				$clusterGroup.push(i);
				for (j=$clusterGroup.length-1; j>=0; j--){
					this._mapMarkers[$clusterGroup[j]]._makeVisible=false;
				}
				this._clusterMarkers.push(this._clusterMarker($clusterGroup));
			}
		}
	}
};

ClusterMarker.prototype._mapTypeChanged=function() {
	this.refresh(true);
};

ClusterMarker.prototype._moveEnd=function(){
	if(!this._cancelMoveEnd){
		this.refresh();
	} else {
		this._cancelMoveEnd=false;
	}
};

ClusterMarker.prototype._preCacheIconBounds=function($indexes){
	var $mapProjection=this._map.getCurrentMapType().getProjection(), $mapZoomLevel=this._map.getZoom(), i, $marker, $iconSize, $iconAnchorPoint, $iconAnchorPointOffset, $iconBoundsPointSw, $iconBoundsPointNe, $iconBoundsLatLngSw, $iconBoundsLatLngNe, $intersectPadding=this.intersectPadding;
	
	for (i=$indexes.length-1; i>=0; i--){
		$marker=this._mapMarkers[$indexes[i]];
		$iconSize=$marker.getIcon().iconSize;
		
		$iconAnchorPoint=$mapProjection.fromLatLngToPixel($marker.getLatLng(), $mapZoomLevel);
		$iconAnchorPointOffset=$marker.getIcon().iconAnchor;
		
		$iconBoundsPointSw=new GPoint($iconAnchorPoint.x-$iconAnchorPointOffset.x-$intersectPadding, $iconAnchorPoint.y-$iconAnchorPointOffset.y+$iconSize.height+$intersectPadding);
		$iconBoundsPointNe=new GPoint($iconAnchorPoint.x-$iconAnchorPointOffset.x+$iconSize.width+$intersectPadding, $iconAnchorPoint.y-$iconAnchorPointOffset.y-$intersectPadding);
		$iconBoundsLatLngSw=$mapProjection.fromPixelToLatLng($iconBoundsPointSw, $mapZoomLevel);
		$iconBoundsLatLngNe=$mapProjection.fromPixelToLatLng($iconBoundsPointNe, $mapZoomLevel);
		
		this._iconBounds[$mapZoomLevel][$indexes[i]]=new GLatLngBounds($iconBoundsLatLngSw, $iconBoundsLatLngNe);
	}
};

ClusterMarker.prototype.refresh=function($forceFullRefresh){
	var i,$marker, $uncachedIconBoundsIndexes;
	$uncachedIconBoundsIndexes=this._filterActiveMapMarkers();
	if (this._activeMarkersChanged || $forceFullRefresh) {
		this._removeClusterMarkers();
		if (this.clusteringEnabled && this._map.getZoom()<this._map.getCurrentMapType().getMaximumResolution()){
			if ($uncachedIconBoundsIndexes.length>0) {
				this._preCacheIconBounds($uncachedIconBoundsIndexes);
			}
			this._filterIntersectingMapMarkers();
		}
		for (i=this._clusterMarkers.length-1; i>=0; i--){
			this._map.addOverlay(this._clusterMarkers[i]);
		}
		for (i=this._mapMarkers.length-1; i>=0; i--){
			$marker=this._mapMarkers[i];
			if (!$marker._isVisible && $marker._makeVisible){
				this._map.addOverlay($marker);
				$marker._isVisible=true;
			}
			if ($marker._isVisible && !$marker._makeVisible){
				this._map.removeOverlay($marker);
				$marker._isVisible=false;
			}
		}
	}
};

ClusterMarker.prototype._removeClusterMarkers=function(){
	for (var i=this._clusterMarkers.length-1; i>=0; i--){
		this._map.removeOverlay(this._clusterMarkers[i]);
	}
	for (i=this._eventListeners.length-1; i>=0; i--){
		GEvent.removeListener(this._eventListeners[i]);
	}
	this._clusterMarkers=[];
	this._eventListeners=[];
};

ClusterMarker.prototype.removeMarkers=function(){
	for (var i=this._mapMarkers.length-1; i>=0; i--){
		if (this._mapMarkers[i]. _isVisible){
			this._map.removeOverlay(this._mapMarkers[i]);
		}
		delete this._mapMarkers[i]._isVisible;
		delete this._mapMarkers[i]._isActive;
		delete this._mapMarkers[i]._makeVisible;
	}
	this._removeClusterMarkers();
	this._mapMarkers=[];
	this._iconBounds=[];
};


ClusterMarker.prototype.triggerClick=function($index) {
	//	a new method to trigger click event on mapMarkers[$index]
	var $marker=this._mapMarkers[$index];
	if ($marker._isVisible) {
		//	$marker is visible so just trigger it's click event
		GEvent.trigger($marker, 'click');
	}
	else if ($marker._isActive) {
		//	$marker is clustered, trigger it's cluster marker's click event and call triggerClick($index)
		var i=0, j=0, $found=false;
		while (!$found) {
			if (this._clusterMarkers[i]._clusteredMarkers[j]==$index) {
				$found=true;
			} else {
				if (j<this._clusterMarkers[i]._clusteredMarkers.length) {
					j++;
				} else {
					i++;
					j=0;
				}
			}
		}
		//	$marker found at clusterMarker[i][j]
		GEvent.trigger(this._clusterMarkers[i], 'click');
		this.triggerClick($index);
	} else {
		// $marker is not within map bounds, pan to or center map on s$marker.getLatLng() and call triggerClick($index)
		this._map.setCenter($marker.getLatLng());
		this.triggerClick($index);
	}
};

ClusterMarker.prototype._zoomEnd=function(){
	this._cancelMoveEnd=true;
	this.refresh(true);
};
